JP2019194504A - Control device and refrigeration system - Google Patents

Abstract

To provide a control device that can keep a temperature in a warehouse lower than a required temperature and a daily electricity bill can be made lower than that when a refrigeration device is operated with a set temperature fixed.SOLUTION: This control device according to the present invention determines a set temperature of a refrigeration device for cooling the inside of a warehouse so that a temperature in the warehouse becomes the set temperature. The control device determines the set temperature for each time zone in which an electricity bill per power consumption amount is different so as to achieve a daily electricity bill of the refrigeration device lower than that when the refrigeration device is operated with the set temperature fixed and for the set temperature to become lower than a required temperature in the warehouse.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a control device that constitutes a refrigeration system together with a refrigeration device that cools the inside of a warehouse, and a refrigeration system including the control device.

  Conventionally, in a refrigeration system provided with a refrigeration apparatus that cools the inside of a warehouse, the refrigeration apparatus is operated so that the inside of the warehouse has a set temperature. At this time, the set temperature is, for example, the same value throughout the day. Here, the basic charge of the electricity charge is determined based on a demand value that is power consumption for 30 minutes. For this reason, the conventional refrigeration system is equipped with demand control that stops the operation of the refrigeration system when the power consumption exceeds the specified value in order to prevent the demand value from exceeding the specified value and increase the basic charge of electricity charges. What to do is also proposed.

  However, the time zone in which the demand control is performed is a time zone in which stored goods are brought into the warehouse and the load reaches a peak. For this reason, when demand control is performed, the temperature in the warehouse rises higher than the required temperature, and there is a concern that the quality of stored items may deteriorate. For this reason, the refrigeration system like patent document 1 is also proposed by the conventional refrigeration system.

  The refrigeration system described in Patent Literature 1 includes a refrigeration apparatus that cools the inside of a warehouse, and a control apparatus that determines a set temperature of the refrigeration apparatus. This control device usually keeps the set temperature constant. Then, the control device predicts a time when the power consumption exceeds a specified value, determines an over-freezing start time that is a predetermined time before the time, and sets the set temperature to be lower than the normal set temperature. Determine refrigeration set temperature. Then, the refrigeration apparatus is operated so that the inside of the warehouse becomes the over-freezing set temperature for a predetermined time from the over-freezing start time. In the refrigeration system described in Patent Document 1, by operating the refrigeration apparatus in this way, the temperature in the warehouse is lowered from the normal temperature before the peak load time, and the temperature in the warehouse rises above the required temperature. To prevent that.

Japanese Patent No. 2913584

  As described above, the refrigeration system described in Patent Document 1 makes the inside of the warehouse cooler than usual before the peak time of the load, and prevents the temperature in the warehouse from rising above the required temperature. . Here, the time zone in which the load reaches a peak, that is, the time zone in which the stored items are carried into the warehouse is mainly daytime. Therefore, in the refrigeration system described in Patent Document 1, the time zone for cooling the warehouse so as to be cooler than usual is mainly daytime. The daytime electricity bill is a time zone during which the electricity bill is high during the day. For this reason, the refrigeration system described in Patent Document 1 has a problem that the electricity cost of one day is higher than when the refrigeration apparatus is operated with the set temperature constant.

  The present invention has been made to solve the above-described problems, can keep the inside of the warehouse lower than the required temperature, and can maintain the set temperature at a constant temperature for a day than when the refrigeration apparatus is operated. A first object is to provide a control device that can reduce the cost of electricity. Moreover, this invention sets it as the 2nd objective to provide the refrigeration system provided with such a control apparatus.

  The control device according to the present invention is a control device that determines the set temperature of a refrigeration apparatus that cools the inside of the warehouse so that the inside of the warehouse becomes a set temperature, and the set temperature is higher than a required temperature in the warehouse. The electricity charge per power consumption is reduced so that the electricity cost per day of the refrigeration apparatus is lower than the electricity cost per day when the refrigeration apparatus is operated at a constant set temperature. The set temperature is determined for each different time zone.

  The refrigeration system according to the present invention includes the control device according to the present invention and a refrigeration device, the refrigeration device having a refrigeration cycle circuit having an indoor heat exchanger for cooling air in the warehouse, and the control. A refrigerating apparatus control device for controlling the refrigerating cycle circuit so that the inside of the warehouse is at the set temperature determined by the apparatus.

  By configuring the refrigeration system using the control device according to the present invention, the inside of the warehouse can be kept lower than the required temperature, and the electricity of the day can be increased compared to when the refrigeration apparatus is operated at a constant set temperature. You can reduce your bill.

It is a figure which shows schematic structure of the refrigeration system which concerns on embodiment of this invention. It is a figure which shows the refrigerating cycle circuit with which the freezing apparatus of the refrigerating system which concerns on embodiment of this invention is provided. It is a block diagram which shows the control apparatus of the refrigerating system which concerns on embodiment of this invention, and the control apparatus for freezing apparatuses. It is a figure which shows an example of the preset temperature for every time slot | zone in the refrigerating system which concerns on embodiment of this invention. It is a figure which shows an example of the preset temperature for every time slot | zone in the refrigerating system which concerns on embodiment of this invention. It is a figure which shows an example of the electricity bill of the day of the refrigeration system which concerns on embodiment of this invention. It is a figure which shows an example of the control flow of the driving | running operation | movement of the refrigerating system which concerns on embodiment of this invention.

  In the following embodiments, an example of a control device according to the present invention and an example of a refrigeration system according to the present invention will be described. Note that the configurations shown in the following embodiments are merely examples. The configurations of the control device and the refrigeration system according to the present invention are not limited to the configurations shown in the following embodiments, and can be appropriately changed without departing from the scope of the invention.

Embodiment.
FIG. 1 is a diagram showing a schematic configuration of a refrigeration system according to an embodiment of the present invention.
In the warehouse 100 whose interior is cooled by the refrigeration system 1 according to the present embodiment, for example, a plurality of storage items 102 are stored. The stored items 102 are frozen foods, refrigerated foods, and the like. The stored item 102 is transported to the outside of the warehouse 100 by means that can be transported at a low temperature, for example, a refrigerator car or a refrigerator car. Then, the stored item 102 is carried into the warehouse 100 through the door 101 of the warehouse 100. The inside of the warehouse 100 is kept below the required temperature by the refrigeration system 1 according to the present embodiment, and the quality of the stored product 102 is ensured. The required temperature is a temperature at which the quality of the stored product 102 does not deteriorate.

  The refrigeration system 1 according to the present embodiment includes the refrigeration apparatus 10 that cools the warehouse 100 so that the interior of the warehouse 100 is lower than the required temperature, and the set temperature that is a control target value of the refrigeration apparatus 10. And a control device 30 for determining.

  The refrigeration apparatus 10 includes an outdoor unit 11 and an indoor unit 12. The outdoor unit 11 is installed outdoors, for example. The indoor unit 12 is installed in the warehouse 100. The outdoor unit 11 and the indoor unit 12 are connected by a refrigerant pipe 13. In addition, the refrigeration apparatus 10 includes a refrigeration apparatus controller 14 that controls the configuration of the refrigeration apparatus 10. The refrigeration apparatus controller 14 is electrically connected to the controller 30. In the present embodiment, the refrigeration apparatus controller 14 is divided into an outdoor unit controller 15 and an indoor unit controller 16. The outdoor unit control device 15 is housed in the outdoor unit 11 and controls the configuration of the outdoor unit 11. The indoor unit control device 16 is housed in the indoor unit 12 and controls the configuration of the indoor unit 12. The outdoor unit control device 15 and the indoor unit control device 16 may be integrated to constitute the refrigeration apparatus control device 14. Details of the control device 14 for the refrigeration apparatus will be described later.

  The refrigeration system 1 according to the present embodiment includes a temperature sensor 2 that detects the temperature in the warehouse 100 and a door opening / closing sensor 3 that detects opening and closing of the door 101 of the warehouse 100. The temperature sensor 2 is, for example, a thermocouple. The number of temperature sensors 2 is arbitrary. For example, when the volume in the warehouse 100 is large and temperature unevenness occurs depending on the location, a plurality of temperature sensors 2 may be arranged in the warehouse 100 in order to grasp the temperature in the warehouse 100 in detail. Various sensors can be used as the door opening / closing sensor 3 as long as it can detect the time during which the door 101 is open. For example, if the door 101 is an automatic door, a sensor that detects a voltage generated in the energization unit when the door 101 is opened and closed can be used as the door opening and closing sensor 3. Further, for example, a camera may be used as the door opening / closing sensor 3 and the opening / closing of the door 101 may be detected by the camera.

FIG. 2 is a diagram showing a refrigeration cycle circuit included in the refrigeration apparatus of the refrigeration system according to the embodiment of the present invention.
The refrigeration apparatus 10 includes a refrigeration cycle circuit 20. Each component of the refrigeration cycle circuit 20 is housed in the outdoor unit 11 or the indoor unit 12.

  Specifically, the refrigeration cycle circuit 20 is configured by connecting a compressor 21, an outdoor heat exchanger 22, an expansion valve 23, and an indoor heat exchanger 24 with refrigerant piping. The refrigerant pipe is, for example, a copper pipe. In order to suppress heat exchange with the ambient air, the refrigerant pipe may be subjected to a heat insulation process such as by winding a heat insulating material.

  The compressor 21 sucks the low-pressure gas refrigerant flowing out from the indoor heat exchanger 24 and compresses it into a high-temperature and high-pressure gas refrigerant. The outdoor heat exchanger 22 is a heat exchanger that functions as a condenser, and condenses the high-temperature and high-pressure gas refrigerant discharged from the compressor 21 into a high-pressure liquid refrigerant. An outdoor fan 25 that supplies outside air to the outdoor heat exchanger 22 is disposed around the outdoor heat exchanger 22. That is, the refrigerant flowing through the outdoor heat exchanger 22 is cooled and condensed by the outside air supplied from the outdoor fan 25.

  The expansion valve 23 expands the high-pressure liquid refrigerant flowing out of the outdoor heat exchanger 22 into a low-temperature and low-pressure gas-liquid two-phase refrigerant. The indoor heat exchanger 24 evaporates the low-temperature and low-pressure gas-liquid two-phase refrigerant that has flowed out of the expansion valve 23 into low-pressure gas refrigerant. An indoor fan 26 that supplies air in the warehouse 100 to the indoor heat exchanger 24 is disposed around the indoor heat exchanger 24. That is, the refrigerant flowing through the indoor heat exchanger 24 is heated and evaporated by the air in the warehouse 100 supplied from the indoor fan 26. In other words, the air in the warehouse 100 is cooled by the refrigerant flowing through the indoor heat exchanger 24.

  In addition, the refrigeration cycle circuit 20 according to the present embodiment includes an accumulator 27 that temporarily stores the refrigerant flowing out of the indoor heat exchanger 24 between the indoor heat exchanger 24 and the compressor 21. If a part of the refrigerant flowing through the indoor heat exchanger 24 cannot evaporate and the gas-liquid two-phase refrigerant flows out of the indoor heat exchanger 24, the gas-liquid two-phase refrigerant flowing into the accumulator 27 is gas in the accumulator 27. It is separated into a refrigerant and a liquid refrigerant. For this reason, by providing the accumulator 27, even if the gas-liquid two-phase refrigerant flows out of the indoor heat exchanger 24, the compressor 21 can suck the gas refrigerant in the accumulator 27.

  Of the configuration of the refrigeration cycle circuit 20, the compressor 21, the outdoor heat exchanger 22, and the accumulator 27 are accommodated in the outdoor unit 11. The outdoor fan 25 is also housed in the outdoor unit 11. The compressor 21 and the outdoor fan 25 are electrically connected to the outdoor unit controller 15. The driving and stopping of the compressor 21 and the driving and stopping of the outdoor fan 25 are controlled by the outdoor unit control device 15. Further, in the case of the compressor 21 having a variable rotation speed during driving, the rotation speed of the driving compressor 21 is also controlled by the outdoor unit control device 15. Similarly, in the case of the outdoor fan 25 in which the rotational speed during driving is variable, the rotational speed of the outdoor fan 25 during driving is also controlled by the outdoor unit control device 15. In the following, for the sake of simplicity, the refrigeration system 1 according to the present embodiment will be described on the assumption that the compressor 21 and the outdoor fan 25 can be driven and stopped at a constant rotational speed.

  Of the configuration of the refrigeration cycle circuit 20, the expansion valve 23 and the indoor heat exchanger 24 are accommodated in the indoor unit 12. The indoor fan 26 is also housed in the indoor unit 12. The expansion valve 23 and the indoor fan 26 are electrically connected to the indoor unit control device 16. The indoor unit controller 16 controls the opening and closing of the expansion valve 23, the opening when the expansion valve 23 is open, and the driving and stopping of the indoor fan 26. In the case of the indoor fan 26 having a variable rotational speed during driving, the rotational speed of the indoor fan 26 being driven is also controlled by the indoor unit control device 16. In the following, in order to simplify the description, the refrigeration system 1 according to the present embodiment will be described on the assumption that the indoor fan 26 can be driven and stopped at a constant rotational speed.

  In the present embodiment, the opening degree of the expansion valve 23 is controlled so that the degree of superheat of the refrigerant flowing out of the indoor heat exchanger 24 becomes a specified value. The degree of superheat of the refrigerant flowing out of the indoor heat exchanger 24 is obtained by subtracting the evaporation temperature of the refrigerant flowing through the indoor heat exchanger 24 from the temperature of the refrigerant flowing out of the indoor heat exchanger 24. Therefore, the refrigeration apparatus 10 according to the present embodiment includes a temperature sensor 29 that detects the temperature of the refrigerant that has flowed out of the indoor heat exchanger 24, and a pressure sensor 28 that detects the pressure of the refrigerant that has flowed out of the indoor heat exchanger 24. And. The temperature sensor 29 and the pressure sensor 28 are electrically connected to the indoor unit control device 16. The temperature sensor 29 is, for example, a thermocouple. The pressure sensor 28 converts, for example, pressure into voltage and outputs it as an electrical signal. The pressure of the refrigerant flowing out of the indoor heat exchanger 24 can be converted into the evaporation temperature of the refrigerant flowing through the indoor heat exchanger 24. For this reason, the indoor unit control device 16 obtains the evaporation temperature from the pressure detected by the pressure sensor 28, subtracts the evaporation temperature from the temperature detected by the temperature sensor 29, obtains the degree of superheat, and the degree of superheat becomes a specified value. In addition, the opening degree of the expansion valve 23 is controlled.

FIG. 3 is a block diagram showing the control device for the refrigeration system and the control device for the refrigeration device according to the embodiment of the present invention.
The control device 30 is configured with dedicated hardware or a CPU (Central Processing Unit) that executes a program stored in a memory. Similarly, the control apparatus 14 for refrigeration equipment is configured by dedicated hardware or a CPU that executes a program stored in a memory. Note that the CPU is also referred to as a central processing unit, a processing unit, an arithmetic unit, a microprocessor, a microcomputer, or a processor.

  When the control device 30 is dedicated hardware, the control device 30 may be, for example, a single circuit, a composite circuit, an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a combination of these. Applicable. Each functional unit realized by the control device 30 may be realized by individual hardware, or each functional unit may be realized by one piece of hardware. Similarly, when the refrigerating apparatus control device 14 is dedicated hardware, the refrigerating apparatus control device 14 corresponds to, for example, a single circuit, a composite circuit, an ASIC, an FPGA, or a combination thereof. Each functional unit realized by the control device 14 for the refrigeration apparatus may be realized by individual hardware, or each functional unit may be realized by one piece of hardware.

  When the control device 30 is a CPU, each function executed by the control device 30 is realized by software, firmware, or a combination of software and firmware. Software and firmware are described as programs and stored in a memory. The CPU implements each function of the control device 30 by reading and executing a program stored in the memory. Similarly, when the refrigeration apparatus control device 14 is a CPU, each function executed by the refrigeration apparatus control device 14 is realized by software, firmware, or a combination of software and firmware. Software and firmware are described as programs and stored in a memory. The CPU implements each function of the refrigeration apparatus controller 14 by reading and executing a program stored in the memory. Here, the memory is, for example, a nonvolatile or volatile semiconductor memory such as a RAM, a ROM, a flash memory, an EPROM, or an EEPROM.

  A part of the function of the control device 30 may be realized by dedicated hardware, and a part may be realized by software or firmware. Similarly, a part of the functions of the control device 14 for the refrigeration apparatus may be realized by dedicated hardware, and a part may be realized by software or firmware.

  The control device 30 according to the present embodiment includes an input unit 31, a storage unit 32, a simulation unit 33, and an output unit 34 as functional units.

  The input unit 31 is a functional unit to which information for determining a set temperature in the warehouse 100 that is a control target value of the refrigeration apparatus 10 is input in the simulation unit 33. The input unit 31 according to the present embodiment receives stored product information, information about the warehouse 100, outside air temperature, cycle characteristics of the refrigeration cycle circuit 20, electricity rate information, and detection results of the door opening / closing sensor 3.

  The stored item information is the amount of the stored item 102 in the warehouse 100. The amount of the stored item 102 in the warehouse 100 may be the amount of the stored item 102 that is actually received / extracted or the amount of the stored item 102 that is scheduled to be stored / extracted. Further, the amount of the storage item 102 scheduled to be loaded / unloaded may use a future loading / unloading schedule or may be predicted from past loading / unloading results. In the present embodiment, the quantity of the stored item 102 is input as the number. The stored product information is the thermal characteristics of the stored product 102. Specifically, the thermal characteristics of the stored item 102 are the amount of cold heat that can be stored in one stored item 102, that is, the amount of cold stored in one stored item 102. The information of the warehouse 100 is a required temperature of the warehouse 100. The information of the warehouse 100 is information for obtaining the amount of heat intrusion from the wall of the warehouse 100 to the inside. In the present embodiment, in order to obtain the amount of heat intrusion from the wall of the warehouse 100 into the interior, the area of the wall of the warehouse 100 in contact with the outside air and the heat passage rate of the wall of the warehouse 100 are input. In the simulation unit 33, the amount of heat intrusion from the wall of the warehouse 100 to the inside is obtained based on the area of the wall of the warehouse 100 in contact with the outside air, the heat transfer rate of the wall surface of the warehouse 100, and the outside air temperature.

  As the outside air temperature, at least a future predicted value up to a time zone in which the set temperature is determined by the simulation unit 33 is input. For example, assume that the current time is in the daytime, and the simulation unit 33 determines the set temperature during the day and the set temperature during the night. In this case, at least the outside temperature until the end of the night is input. The cycle characteristic of the refrigeration cycle circuit 20 is information for obtaining electric power consumed when the refrigeration cycle circuit 20 exhibits a predetermined refrigeration capacity. The electricity rate information is an electricity rate per power consumption for each time zone of the day. For example, in Japan, the electricity charge per power consumption may differ between daytime and nighttime. In this case, as the electricity rate information, an electricity rate per hour during the daytime and an electricity rate per hour during the nighttime are input.

  Further, the temperature detected by the temperature sensor 2 is also input to the input unit 17. The operating state of the refrigeration apparatus 10 is also input to the input unit 17 from an output unit 19 described later of the refrigeration apparatus controller 14. The input unit 17 also receives an operation start command and an operation end command for the refrigeration system 1 from, for example, a user of the refrigeration system 1.

  In addition, the input of each information to the input part 17 may be performed manually, and the structure input automatically from another system may be sufficient. For example, when the entry / exit information of the storage item 102 is managed by the entry / exit management system, the storage item information can be automatically input from the entry / exit management system to the input unit 17. Further, for example, information on the warehouse 100 can be automatically input to the input unit 17 from CAD data or the like of construction drawings. Further, for example, the outside air temperature can be automatically input from the weather data to the input unit 17. Further, for example, the cycle characteristics of the refrigeration cycle circuit 20 can be automatically input from the capacity characteristic data of the refrigeration apparatus 10 to the input unit 17. Electricity rate information can be automatically input if a configuration is adopted in which a rate plan such as a web site of a contracted electric power company is input to the input unit 17. Moreover, when inputting each information to the input part 17 manually, the control apparatus 30 may be provided with input display apparatuses, such as a touchscreen, as a user interface.

  The storage unit 32 is a functional unit that stores information input to the input unit 17 and information necessary when the simulation unit 33 performs a simulation.

  Based on the information stored in the storage unit 32, the simulation unit 33 can maintain the temperature within the warehouse 100 below the required temperature throughout the day, and can set the set temperature for each time zone with different electricity charges per power consumption. This is a functional unit obtained by simulation. At this time, there are many combinations of set temperatures for each time period that can satisfy the condition that the inside of the warehouse 100 can be kept below the required temperature throughout the day. Therefore, the simulation unit 33 determines that the daily electricity cost of the refrigeration apparatus 10 is higher than the daily electricity cost when the refrigeration apparatus 10 is operated at a constant set temperature from among combinations of the set temperatures for each time zone. Select a combination that will be cheaper. And the simulation part 33 determines the setting temperature of the said combination to the setting temperature for every time slot | zone from which the electricity bill per power consumption differs. In the present embodiment, as will be described later, the simulation unit 33 sets the set temperature of the combination at which the daily electricity bill is the lowest among the combinations of the set temperatures for each time zone, per power consumption. Determine the set temperature for each time zone with different electricity charges.

  The output unit 34 is a functional unit that outputs the set temperature for each time period determined by the simulation unit 33 to the input unit 17 (to be described later) of the refrigeration apparatus controller 14. In addition, the control part 18 mentioned later of the control apparatus 14 for refrigeration apparatuses controls the compressor 21, the outdoor fan 25, and the indoor fan 26 using the detected temperature of the temperature sensor 2. FIG. For this reason, the output unit 34 also outputs the temperature detected by the temperature sensor 2 to the input unit 17 (to be described later) of the refrigeration apparatus controller 14.

The refrigeration apparatus controller 14 according to the present embodiment includes an input unit 17, a control unit 18, and an output unit 19 as functional units.
The input unit 17 is a functional unit to which the set temperature for each time zone determined by the simulation unit 33 and the detected temperature of the temperature sensor 2 are input from the output unit 34 of the control device 30. Further, the detection temperature of the temperature sensor 29 and the detection pressure of the pressure sensor 28 are also input to the input unit 17.

  The control unit 18 includes the compressor 21, the expansion valve 23, the outdoor fan 25, and the indoors of the refrigeration apparatus 10 so that the set temperature is input to the input unit 17 in each time zone in which the electricity rate per power consumption is different. The fan 26 is controlled. Specifically, during the operation of the refrigeration apparatus 10, the control unit 18 stops the compressor 21, the outdoor fan 25, and the indoor fan 26 when the temperature detected by the temperature sensor 2 becomes lower than the set temperature. Moreover, the control part 18 drives the compressor 21, the outdoor fan 25, and the indoor fan 26, when the detected temperature of the temperature sensor 2 becomes higher than preset temperature. During operation of the refrigeration apparatus 10, the control unit 18 obtains the evaporation temperature from the pressure detected by the pressure sensor 28, subtracts the evaporation temperature from the temperature detected by the temperature sensor 29 to obtain the degree of superheat, and the degree of superheat is defined. The opening degree of the expansion valve 23 is controlled so as to be a value.

  The output unit 19 outputs to the input unit 17 of the control device 30 whether or not the refrigeration apparatus 10 is operating.

  In addition, in this Embodiment, the control apparatus 30 and the control apparatus 14 for refrigeration apparatuses are comprised separately, but you may comprise the control apparatus 30 and the control apparatus 14 for refrigeration apparatuses integrally.

  Next, the operation of the refrigeration system 1 will be described.

First, operation | movement of the freezing apparatus 10 at the time of cooling the air in the warehouse 100 is demonstrated.
When the refrigeration apparatus 10 is operated and the compressor 21 is driven, low-pressure gas refrigerant is sucked into the compressor 21 and is discharged from the compressor 21 as high-temperature and high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 21 flows into the outdoor heat exchanger 22. The high-temperature and high-pressure gas refrigerant that has flowed into the outdoor heat exchanger 22 is cooled and condensed by the outside air supplied from the outdoor fan 25 to become a high-pressure liquid refrigerant. This high-pressure liquid refrigerant flows out of the outdoor heat exchanger 22 and flows into the expansion valve 23.

  The high-pressure liquid refrigerant that has flowed into the expansion valve 23 expands in the expansion valve 23 and becomes a low-temperature low-pressure gas-liquid two-phase refrigerant. This low-temperature low-pressure gas-liquid two-phase refrigerant flows into the indoor heat exchanger 24 and flows through the indoor heat exchanger 24. On the other hand, as the indoor fan 26 rotates, the air in the warehouse 100 is sucked into the indoor unit 12 and the sucked air is supplied to the indoor heat exchanger 24. Due to the supplied air, the low-temperature and low-pressure gas-liquid two-phase refrigerant flowing through the indoor heat exchanger 24 is heated and evaporated to become a low-pressure gas refrigerant. In other words, the air in the warehouse 100 sucked into the indoor unit 12 is cooled by the refrigerant flowing through the indoor heat exchanger 24. Then, the air cooled by the refrigerant flowing through the indoor heat exchanger 24 is blown out from the indoor unit 12 into the warehouse 100 by the rotation of the indoor fan 26. Thereby, the inside of the warehouse 100 is cooled.

  The low-pressure gas refrigerant in the indoor heat exchanger 24 flows out of the indoor heat exchanger 24, passes through the accumulator 27, and is then sucked into the compressor 21.

  When the temperature detected by the temperature sensor 2, that is, the temperature in the warehouse 100 becomes lower than the set temperature during the operation of the refrigeration apparatus 10, the compressor 21, the outdoor fan 25, and the indoor fan 26 are stopped. Thereafter, when the temperature detected by the temperature sensor 2, that is, the temperature in the warehouse 100 becomes equal to or higher than the set temperature, the compressor 21, the outdoor fan 25, and the indoor fan 26 are driven again. During the operation of the refrigeration apparatus 10, the opening degree of the expansion valve 23 is controlled so that the degree of superheat of the refrigerant flowing out from the indoor heat exchanger 24 becomes a specified value.

  Next, a method for determining the set temperature for each time zone with different electricity charges per power consumption performed by the simulation unit 33 will be described.

4 and 5 are diagrams showing an example of the set temperature for each time zone in the refrigeration system according to the embodiment of the present invention.
The daily electricity bill Y [yen] of the refrigeration apparatus 10 can be obtained by the following equation (1).
Y = Y1 × W1 + Y2 × W2 (1)
Here, Y1 is the electricity bill [yen / kWh] per nighttime power consumption. W1 is the power consumption [kWh] at night. Y2 is an electricity bill [yen / kWh] per daytime power consumption. W2 is the daytime power consumption [kWh]. The above equation (1) is stored in the storage unit 32.

  The nighttime electricity rate Y1 [yen / kWh] and the daytime electricity rate Y2 [yen / kWh] differ according to the timing and contract type, but generally the nighttime electricity rate Y2 [yen / kWh] Y1 [yen / kWh] is cheaper. For this reason, for example, when there are many stored items 102 in the warehouse 100 and a large amount of cold energy can be stored in the stored items 102, for example, by determining a set temperature for each time zone as shown in FIG. In some cases, the electricity bill Y [yen] can be reduced.

  Specifically, the set temperature is lowered in the night time zone when the electricity rate is cheap, and the operating rate of the night refrigeration apparatus 10 is increased. Then, cold energy is stored in the storage product 102 and the wall of the warehouse 100. On the other hand, during the daytime, the set temperature is raised higher than at night. And during the daytime, the cold storage stored in the storage goods 102 and the wall of the warehouse 100 is used to prevent the inside of the warehouse 100 from becoming higher than the required temperature. When there are many stored items 102 in the warehouse 100 and a large amount of cold heat can be stored in the stored items 102, for example, by determining the set temperature for each time zone as described above, the inside of the warehouse 100 is reduced to a required temperature or less. In some cases, the electricity bill Y [yen] can be reduced while maintaining.

  Further, for example, when the amount of stored goods 102 in the warehouse 100 is small, and when the difference between the nighttime electricity charge Y1 [yen / kWh] and the daytime electricity charge Y2 [yen / kWh] is small, for example, As shown in FIG. 5, by determining the set temperature for each time zone, the electricity bill Y [yen] may be able to be reduced. Specifically, in the night time period when the amount of heat entering the warehouse 100 from the outside is small, the operating temperature of the refrigeration apparatus 10 is lowered by raising the set temperature compared to the day time period. For example, when the amount of the stored item 102 in the warehouse 100 is small, or when the difference between the nighttime electricity rate Y1 [yen / kWh] and the daytime electricity rate Y2 [yen / kWh] is small, for example, By determining the set temperature for each time zone, it may be possible to reduce the electricity bill Y [yen] while maintaining the warehouse 100 at or below the required temperature.

  Therefore, in the refrigeration system 1 according to the present embodiment, the simulation unit 33 simulates the transfer of heat in the warehouse 100 using environmental conditions that change from moment to moment, and the above equation (1) is used for one day. The set temperature is determined for each time zone in which the electricity bill Y [yen] is the cheapest.

  Specifically, the amount of heat that the refrigeration apparatus 10 cools is the sum of the amount of heat for cooling the stored item 102 and the amount of heat for cooling the amount of heat that enters the warehouse 100 from the outside. For this reason, if the change in the amount of heat necessary for cooling the stored goods 102 in the day and the change in the amount of heat entering the warehouse 100 from the outside in the day are known, It can be seen that the amount of heat that the refrigeration apparatus 10 cools in order to maintain a set temperature lower than the required temperature during the day.

  As for the amount of heat for cooling the stored item 102, if it is known when and how much of the stored item 102 with what thermal characteristic is received and stored, the amount of heat for cooling the stored item 102 that changes every moment is obtained. be able to. In addition, when performing a simulation using the amount of stored goods 102 that has actually been entered and exited, if the simulation is performed a plurality of times during the day, the amount of heat for cooling the stored goods 102 that changes from time to time can be obtained. it can.

  A change in the amount of heat entering the warehouse 100 from outside can be obtained from information on the warehouse 100 and information on the outside air temperature. In addition, since the refrigeration system 1 according to the present embodiment includes the door opening / closing sensor 3, when the door 101 is opened when the stored item 102 is loaded or unloaded from the outside temperature and the opening / closing time of the door 101, the warehouse is externally stored. The amount of heat that enters into 100 can also be grasped. For this reason, the change in the amount of heat entering the warehouse 100 from the outside can be obtained more accurately. The opening / closing time of the door 101 may be predicted from the amount of goods stored / stored without the door opening / closing sensor 3.

  If the change in the amount of heat that the refrigeration apparatus 10 that is necessary for maintaining the interior of the warehouse 100 at the set temperature cools in one day is known, the change in the refrigeration capacity of the refrigeration apparatus 10 that is required per unit time in the day Recognize. The electric power required to obtain a predetermined cooling capacity varies depending on the outside air temperature or the like, but can be obtained from the cycle characteristics of the refrigeration cycle circuit 20.

  For example, by simulating in this way, a change in power consumption during the day can be obtained. That is, it can be seen how much power consumption for each time period with different electricity charges per power consumption can be maintained in the warehouse 100 at a set temperature lower than the required temperature. In addition, the specific method of simulation is not specifically limited. Conventionally, various simulations have been proposed for determining changes in power consumption during a day in a refrigeration system or the like that reduces power consumption. What is necessary is just to obtain | require the change of the power consumption in one day using these simulations.

  There are a plurality of combinations of power consumption for each time period in which the inside of the warehouse 100 can be maintained at the set temperature. From these combinations, the simulation unit 33 uses formula (1) to select the power consumption for each time period in which the daily electricity bill Y [yen] is the cheapest. And the simulation part 33 determines the preset temperature used as the selected electric power consumption to the preset temperature for every time slot | zone.

  Note that the basic electricity charge is determined based on a demand value that is power consumption for 30 minutes. For this reason, the simulation part 33 may select the power consumption for every time slot | zone so that the demand value used as the calculation reference | standard of an electric basic charge may not be exceeded. That is, the simulation unit 33 may determine the set temperature for each time period so as not to exceed the demand value that is the calculation standard for the basic electricity bill. Thereby, the electricity bill of the day can be further reduced. In this case, the demand value is stored in the storage unit 32 as electricity rate information.

  FIG. 6 is a diagram showing an example of a daily electricity bill of the refrigeration system according to the embodiment of the present invention. In addition, the continuous line shown in FIG. 6 is the electricity bill for one day of the refrigeration system 1 which concerns on this Embodiment. Moreover, the broken line shown in FIG. 6 is the electricity bill for one day of the refrigeration system which concerns on a comparative example. Further, the refrigeration system according to the comparative example operates the refrigeration apparatus 10 at a constant set temperature. FIG. 6 shows the electricity bill for one day when there are a relatively large number of stored items 102 in the warehouse 100.

  As shown by the broken line in FIG. 6, the refrigeration system according to the comparative example operates the refrigeration apparatus 10 at a constant set temperature, so that the electricity bill increases during the day when the amount of heat entering the warehouse 100 increases. The electricity bill for the day is high. On the other hand, in the case of the refrigeration system 1 according to the present embodiment, the set temperature is lowered in the night time zone where the electricity bill is cheap, and the operating rate of the night refrigeration apparatus 10 is increased. For this reason, the refrigeration system 1 according to the present embodiment has a higher electricity bill at night than the refrigeration system according to the comparative example. However, since the refrigeration system 1 according to the present embodiment can store cold energy in the stored item 102 at night, by using the cold energy during the daytime, the set temperature during the day can be set higher than that at night. Even if the temperature is raised, the inside of the warehouse 100 can be prevented from becoming higher than the required temperature. Therefore, the refrigeration system 1 according to the present embodiment can suppress an increase in the daytime electricity bill, and can be made cheaper than the refrigeration system according to the comparative example in the one day electricity bill.

  Finally, an example of the control flow of the operation operation of the refrigeration system 1 according to the present embodiment will be introduced. In the following, an example of the control flow of the operation operation of the refrigeration system 1 will be introduced, taking as an example the case where the electricity rate per power consumption differs between daytime and nighttime.

FIG. 7 is a diagram illustrating an example of a control flow of the operation operation of the refrigeration system according to the embodiment of the present invention.
In step S1, an operation start command for the refrigeration system 1 is input from, for example, a user of the refrigeration system 1. In step S <b> 2, the simulation unit 33 of the control device 30 acquires information necessary for determining the set temperature for each time zone from the storage unit 32. In step S3, the simulation unit 33 determines a set temperature for each time period. Specifically, if execution of step S3 is nighttime, the simulation unit 33 determines a set temperature for a night time zone and a set temperature for a daytime time zone after the night time zone. If the execution of step S3 is daytime, the simulation unit 33 determines the set temperature for the daytime time zone and the set temperature for the nighttime time zone after the daytime time zone.

  In step S4, the control unit 18 of the refrigeration apparatus 10 starts the operation of the refrigeration apparatus 10. In step S5 after step S4, the control unit 18 of the refrigeration apparatus 10 determines whether the temperature detected by the temperature sensor 2 is lower than the set temperature. That is, step S5 is a step of determining whether the temperature in the warehouse 100 is lower than the set temperature. In addition, when step S5 is performed in the night time zone, the control unit 18 compares the detected temperature of the temperature sensor 2 with the set temperature in the night time zone. When Step S5 is executed during the daytime, the control unit 18 compares the temperature detected by the temperature sensor 2 with the set temperature during the daytime.

  When the detected temperature of the temperature sensor 2 is lower than the set temperature in step S5, the control unit 18 of the refrigeration apparatus 10 stops the operation of the refrigeration apparatus 10 in step S6. That is, the control unit 18 of the refrigeration apparatus 10 stops the compressor 21, the outdoor fan 25, and the indoor fan 26.

  Step S7 after step S6 is a step of determining whether an operation end command for the refrigeration system 1 is input to the input unit 31 of the control device 30 from, for example, a user of the refrigeration system 1 or the like. When the operation end command is input, the operation of the refrigeration system 1 ends. When the operation end command is not input, the process returns to step S5, and step S5 and subsequent steps are repeated.

  On the other hand, when the detected temperature of the temperature sensor 2 is equal to or higher than the set temperature in step S5, the control unit 18 of the refrigeration apparatus 10 determines whether or not a certain time has passed in step S6. If the certain time has not elapsed, the process returns to step S5. On the other hand, if the detected temperature of the temperature sensor 2 is equal to or higher than the set temperature even after a predetermined time has elapsed, the process returns to step S2. In step S3, the set temperature is determined again, and step S4 and subsequent steps are repeated.

  As described above, the control device 30 according to the present embodiment is a control device that determines the set temperature of the refrigeration apparatus 10 that cools the inside of the warehouse 100 so that the inside of the warehouse 100 becomes the set temperature. The control device 30 then sets the set temperature to be lower than the required temperature in the warehouse 100, and the refrigeration apparatus 10 has one day of electricity more than the one-day electricity bill when the refrigeration apparatus 10 is operated at a fixed set temperature. The set temperature is determined for each time zone in which the electricity rate per power consumption is different so that the electricity bill of the product is reduced.

  In addition, the refrigeration system 1 according to the present embodiment includes a control device 30 and a refrigeration device 10 according to the present embodiment. In addition, the refrigeration apparatus 10 includes the refrigeration cycle circuit 20 having the indoor heat exchanger 24 that cools the air in the warehouse 100, and the refrigeration cycle circuit 20 so that the inside of the warehouse 100 reaches the set temperature determined by the control device 30. And a control device 14 for the refrigeration apparatus to be controlled.

  As described above, by configuring the refrigeration system 1 using the control device 30 according to the present embodiment, the inside of the warehouse 100 can be kept lower than the required temperature, and the refrigeration apparatus 10 can be set at a constant set temperature. You can make your daily electricity bill cheaper than when you drive.

  In addition, the refrigeration system 1 according to the present embodiment is more efficient than the refrigeration system in which the power consumption is reduced by determining the set temperature for each time period in which the electricity rate per power consumption differs as described above. The electricity bill for the day can be reduced. At this time, the refrigeration system 1 according to the present embodiment may increase the daily power consumption as compared with the refrigeration system that reduces the power consumption.

  Further, the parameters (variables) used in the simulation of the simulation unit 33 in the present embodiment are merely examples.

  For example, when the stored item 102 is carried into the warehouse 100, the temperature of the stored item 102 may be higher than the set temperature of the warehouse 100. In such a case, the stored product 102 brings the amount of heat of the temperature difference with respect to the set temperature into the warehouse 100. For this reason, for example, in the simulation of the simulation unit 33, the amount of heat of the stored item 102 may be used as a parameter.

  Further, for example, in the simulation of the simulation unit 33, the temperature distribution in the warehouse 100 may be used as a parameter. Specifically, for example, the temperature distribution in the warehouse 100 can be used as a parameter as follows. When a plurality of temperature sensors 2 are arranged in the warehouse 100, the temperature distribution in the warehouse 100 can be known. For example, when determining the set temperature for each time zone with different electricity charges per power consumption by simulation, the temperature sensor 2 that has detected the highest temperature may be simulated so that the detected temperature becomes the set temperature. For example, as a conventional simulation method for obtaining the amount of heat that enters the warehouse 100 from the outside, there is a method that uses the temperature in the warehouse 100 in addition to the information on the outside air temperature and the information on the warehouse 100. In such a simulation, an average value of the detected temperatures of the plurality of temperature sensors 2 may be used as the temperature in the warehouse 100. By using the temperature distribution in the warehouse 100 as a parameter in the simulation of the simulation unit 33, it is possible to perform a simulation in consideration of temperature unevenness in the warehouse 100.

  Further, for example, among the parameters used in the simulation of the simulation unit 33, those having a small fluctuation amount may be fixed values.

  For example, when the electricity rate for each time zone does not change with time, the electricity rate may be stored in the storage unit 32 as a fixed value, and the simulation in the simulation unit 33 may be performed. Further, for example, there are various items in the stored item 102 stored in the warehouse 100. When the amount of cold storage of each item is approximate, the cold storage amount per one stored item 102 is set as a fixed value. You may memorize | store in the memory | storage part 32 and perform the simulation in the simulation part 33. FIG. In addition, for example, when approximately the same amount of stored goods 102 is loaded and unloaded at approximately the same time every day, the opening / closing time of the door 101 is stored in the storage unit 32 as a fixed value, and the simulation unit 33 performs a simulation. May be.

  Further, for example, when the warehouse 100 is installed in a place where there is little variation in the outside air temperature due to the season, the amount of heat intrusion from the wall of the warehouse 100 to the inside is stored in the storage unit 32 as a fixed value, and the simulation unit 33 You may perform a simulation. Further, for example, when the warehouse 100 is installed in a place where there is little variation in the outside air temperature due to the season, the predicted value of the outside air temperature is stored in the storage unit 32 as a fixed value, and the simulation in the simulation unit 33 is performed. Also good. And you may change the fixed value of the predicted value of outside temperature for every season.

  Further, although the refrigeration system 1 according to the present embodiment includes one refrigeration apparatus 10, the number of the refrigeration apparatuses 10 included in the refrigeration system 1 is arbitrary. What is necessary is just to determine suitably the number of the freezing apparatuses 10 with which the refrigerating system 1 is provided according to the magnitude | size in the warehouse 100. FIG. Moreover, when the temperature irregularity in the warehouse 100 is large, the indoor unit 12 that can be locally cooled may be used to cool a portion where the temperature locally increases in the warehouse 100.

  Moreover, the outdoor unit 11 and the indoor unit 12 of the refrigeration apparatus 10 are not necessarily air-cooled. For example, a water-cooled heat exchanger may be provided in the outdoor unit 11 and the indoor unit 12.

  DESCRIPTION OF SYMBOLS 1 Refrigeration system, 2 Temperature sensor, 3 Door opening / closing sensor, 10 Refrigeration apparatus, 11 Outdoor unit, 12 Indoor unit, 13 Refrigerant piping, 14 Control apparatus for freezing apparatus, 15 Outdoor unit control apparatus, 16 Indoor unit control apparatus, 17 Input Part, 18 control part, 19 output part, 20 refrigeration cycle circuit, 21 compressor, 22 outdoor heat exchanger, 23 expansion valve, 24 indoor heat exchanger, 25 outdoor fan, 26 indoor fan, 27 accumulator, 28 pressure sensor, 29 temperature sensor, 30 control device, 31 input unit, 32 storage unit, 33 simulation unit, 34 output unit, 100 warehouse, 101 door, 102 storage goods.

Claims (9)

A control device for determining the set temperature of the refrigeration apparatus for cooling the inside of the warehouse so that the inside of the warehouse becomes a set temperature,
The set temperature is lower than the required temperature in the warehouse, and the daily electricity cost of the refrigeration apparatus is lower than the daily electricity cost when the refrigeration apparatus is operated with the set temperature constant. So that
The control apparatus which determines the said setting temperature for every time slot | zone from which the electricity bill per power consumption differs.   The control device according to claim 1, wherein the set temperature for each of the time zones is determined by a simulation using a quantity of stored items in the warehouse as a parameter.   The control device according to claim 2, wherein the set temperature for each of the time periods is determined so as not to exceed a demand that is a calculation standard for an electric basic charge.   The control device according to claim 2, wherein the simulation uses a cold storage amount of the stored item as a parameter.   The control device according to any one of claims 2 to 4, wherein the simulation uses an amount of heat of the stored product as a parameter.   The control device according to any one of claims 2 to 5, wherein the simulation uses a predicted value of an outside air temperature as a parameter.   The control device according to any one of claims 2 to 6, wherein the simulation uses an opening / closing time of the warehouse door as a parameter.   The control device according to any one of claims 2 to 7, wherein the simulation uses a temperature distribution in the warehouse as a parameter. The control device according to any one of claims 1 to 8,
A refrigeration device;
With
The refrigeration apparatus is
A refrigeration cycle circuit having an indoor heat exchanger for cooling the air in the warehouse;
A control device for a refrigeration system that controls the refrigeration cycle circuit so that the inside of the warehouse is at the set temperature determined by the control device;
Refrigeration system with.

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